I have lived five years in Saudi Arabia, two in Iran, and two in Indonesia. There are variations in how countries and people practice Islam, but the Koran is still central to the daily lives of the individual. When you pray five times a day, fast for a month, and make a pilgrimage to Mecca, you are far more involved with your religion than most Christians or Jews. In many ways Islam is more akin to a cult than a religion. Apostates are treated harshly.
Perhaps it is Buchanan's reflexive anti-Zionism (I deliberately did not say anti-Semitism) or his isolationist proclivities, but he seems to have got this wrong. I take seriously your observations concerning the mindset of Islam because it is confirmatory of what we have heard from other sources. I do not believe that Netanyahu is so exercised about the situation for no reason.
But it does not take a fanatical Muslim to be self-destructive. Consider the fanaticism of the Japanese in World War II, consider the degree of self-sacrifice and destruction they were willing to endure. Consider the degree of suffering borne by the Germans under Nazi administration in World War II. When you have tens of thousands of people dying every night in Japan and in Germany and those administrations nevertheless carrying on the war when it was utterly hopeless, we have a mindset that is not far from inviting Armageddon.
We must understand that this situation is not put to a plebiscite in Iran, rather it is the policy of a theocracy. Consider the fanaticism of those who ruled Japan, we consider them to be militarists but it was also in a sense a theocracy in that the Emperor was considered divine and the "militarists" were in a sense his apostles. No one can deny that Nazi-ism was a kind of secular religion and that Hitler himself enjoyed a super human charismatic reputation among the Germans.
It does not take the whole of Iran to make a conscious decision to invite Armageddon to gain the gates of Allah's paradise, it requires only the fixed determination of a few fanatical mullahs in custody of the bomb.